The X5D is basically the same as the regular X5 (see X5 review) - with some added whistles and bells. The polyphony has been expanded to 64 voices (32 in double mode), there are 2 MB more samples onboard (total 8 MB) and also some other nice little enhancements.

Scott : A good solid entry level keyboard, with 64 voice poly...a nice machine for multimedia composing. (Includes a serial interface in addition to MIDI in/out/thru built in.) Keyboard is so-so, but the unit is very light and compact, so it's a good travelling companion.

Excellent effects are fun to play with. The user interface, despite an occasional quirk, won me over...I sensed it was a fun machine to play, and I was right. I've been very satisfied with it